In the past I have attached the piezo to metal plates with thin double sided tape.
This worked well but it always bugged me that there was a layer of tape between the piezo and the metal.
Today I tried hot glue.
In the past I have always had problems even using hot glue. Was always like it would cool down too much before I got to push on the bit to be glued.
So today I cut of a small peice the hot glue, set it on the metal and applied a hair drier to it to melt it to liquid. The plate got so hot I could not touch it, the glue melted to liquid, but when I applied the piezo, it cooled do such that pushing down on the pizeo, i broke it.
So I tried again. My last piezo. I broke that one too. Ideally I wanted the piezo to push the glue out on all sides. But once again the glue cooled too quickly and was a solid lump in the middle of the piezo. Press down on it broke it.
Can anyone offer some advice on this? Maybe glue under the piezo is the wrong approach. Perhaps I should just put the piezo on the metal and put glue all around it to hold it down. Sound like a plan? Or is there a better way to attach them?